Glare-preventive means for headlights.



J. B. MORRISON GLARE PREVENTIVE mums FOB HEADLIGHTS.

APPMOATIOH FILED AUG.24.1914.

Patented Mar. 23, 1915.

Witnaoow rrn IQHN EDWARD MORRISON, 0F MEMPHIS, TENNESSEE, ASSIGNOR 'IQSA'FET-LITE (30.,

OF MEMPHIS, TENNESSEE. A CORPORATION Q TENNESSEE.

GLABE-PREVENTIVE MEANS FEB, HEADLIGHTS.

asascs.

Specification of Letters Yatent.

Patented Mar. 23, 19K 5.

Continuation in part of application Serial. Z-Ie. 848,602, filed July 2,1914. This application filed august fie, 191%. Serial No. 858,286.

To all whom it "may concern Be it lrnownthat l, Mounison, a citizen of.the United States, residing at Memphis, in the county of Shelby andState of Tennessee, have invented a new and useful Glare-PreventiveMeans for Headlights, of which the following is a specification.

This invention has reference to glare preventive means for headlightsand the like, and is especially designed for use in connection withautomobile headlights of l igh power so as to tone down or eliminate theglare of the headlight without to any marked light-giving means withinthe headlight is directed throughout a circumscribed area extentreducing the efficiency of the emitted cone of light throughout itsentire crosssectioilal area. i

The present invention comprises means which may form a permanent part ofthe headlight structure or may be separately made and applied to theheadlight as an attachment, and the structure is such that the fullforce of the light as emitted from the where'il'lumination is mostneeded, and also where it will not reach the eye of the ob server infront of the headlight either directly or by reflection from the usualreflector within the headlight, while the remainder of the cone ofillumination receives practically the same amount of light that it Wouldif the device of the present invention were absent, but the light is so"diffused as to be unobtrusive to the eye of the observer hecause'of theelimination of allglare. This is brought about by the interposition oflight diffusive means of less area than the light emitting opening ofthe headlight be tween the light emitting unit, which is usually anacetylene burner or an incandescent electric bulb, or in some instancesan electric arc light, and the eye of the observer, the area andlocation of the light diffusive means being such as to intercept rays oflight which would otherwise reach the eye of the observer by reflection,as well as those 1 which would otherwise reach the eye of the side ofthe headlight.

left at the lower portion of the light emitting observer directly, andthis whether the observer be in front of or more or less to one Thereis, however,

which the rays of light pass with full intensity to illuminate a portionof the roadway ahead of the vehicle and which rays of light underconditions of use are at too low a level to reach the eye of theobserver approaching the headlight or toward whom the headlight moves.

While the present invention has wide applicability, being useful inconnection with any light projecting apparatus where the glare of thelight source of great intensity is liable to be troublesome, theinvention is particularly useful in connection with auto-'' changed andmodified so long as such changes and modifications mark no materialdeparture from the salient features of the invention.

In the drawings :Figure 1 is a front elevation of an automobileheadlight provided with the invention, some parts being broken away toshow more distant parts. Fig. 2 is a section on the line 2 2 of Fig. 1.some parts being shown in elevation.- Fig. 3 is a front elevation withparts in section of'an embodiment of the invention adaptable as anattachment to a headlight. Fig. 4 is a (link metric front to rearsectionof a. modified form of lihe invention. Figs. 5 and 6 are elevations" "ofother modified forms of the in vention.

Referring to the drawings there is shown a headlight 1 which may betaken as indicative of any type of headlight customarily employed inconnection with automobiles and other motor vehicles. As the particularconstruction of the headlight does not enter into the present inventionit is not described in detail. I

In Figs. 1 and 2 the headlight is shown as provided with a front lens 2,as is customary with some forms of headlights, but it will be understoodthat. this front member 2 is to be taken as indicative of any frontglass -such as is used in connection with automo- 'glassbe lens-like orplane;

with such a headlight structure as is shown bile or other headlightswhether such front In connection tion of the plate and merges into theperipheral portion of the plate by reverse-curve portions 4. The plate 3is mounted in a channel ring 5 leaving'between the main body of theplate 3 with the rounded projection 4 and that portion of the ring 5 notoccupied by the plate 3 a curved or areshaped opening 6 of less than 180degrees circumferential extent. The plate 3 with its border ring orcarrying ring 5 is mounted within the headlight casing immediately backof the frontglass 2 where it is held by clips 7 like those usually emloyed for retaining the front glass 2 in p ace, 'a'nd these clips may{LlSOSQlVe to hold such front glass in place. course, other means forhold ingrthe plate 3 in place maybe used.

or preventing the plate 3 from turning in the ring 5 the latter iscrimped, as shown at 8, or may be otherwise formed immediately adjacentto the end'portions of the chord part of the body of the plate 3.

It is not essential that the projection 4 merge into the chord portionof the plate 3 by curves 4, since these portions may be straight, asshown at 4" in Fig. 5.

In the forms 'of the plate 3 shown in Figs. 1, 2, 3 and 5 the entireplane area of, the plate is made light dijfusiye by sand-blasting orotherwise grinding one or both' faces, the ground glass surface beingindicated at 9.

Where the light diffusive surface is produced directly upon the frontglass of the headlight such glass is then of full circular form, but theground portion with the dip art 4 is of less'area. In Fig. 4 a lens-likerout glass 2*.is shown and upon one face of this front glass 2" is aground glass area 9 which may agree in extent .Witheither the showing ofFigs. 3 or 5 or may have other conformation such as indicated in Fig; 6where there is a dip portion or projection P of generally triangularshape instead of rounded form like the showing of Figs. 1, 3 and 5. InFig. 6 there is a clear portion 6 which though not truly concentriconits upper edge with the plate indicated at 3 of Fig. 6, issufficiently near an approach to are shape to be considered as generallyare ortion showing of Figs. 1, 2 and 4.

The ground glass portion of the headlight may be and preferably is ofpractically even character and density throughout and the unground orplain portion is practically nondilfusive and unobstructive to thepassage of light.

With the highest power headlights it is advisable to produce the groundglass surface upon both faces of either the front glass of.the headlightor the supplemental plate when the latter is employed, but with thelower power headlights, say, those employing acetylene burners, thegrinding of one face of the front or supplemental plates, whichever beused, is sutiicient. It will also be understood that where only onesurface is rendered light diffusive by grinding, sandblasting, or othertreatment, it is the front surface that is so treated, since a polishedfront surface is liable to cause objectionable glare were thesand-blasting or other treatment produced upon the rear surface insteadof the front surface.

The ordinary high power headlight with a. clear glass front projects anintensely brilliant cone of light many hundred feet in advance of thevehicle,.and is so dazzling to observers in front of the vehicle as tointerfere seriously with traflic, the blinding light so produced causingmany serious ac cidents.

\Vith the present invention the blinding glare of the headlight which isdue to a large extent to the presence of the reflector is for allpractical purposes whollyelimi nated, but, at the same time, theilluminating effect of the headlight is not to any marked extentdiminished. To the occir pants of the vehicle an ordinarily dark roadwayis brilliantly illuminated to an extent so nearly approaching theillumination afforded by headlights unequipped with the presentinvention that the presence of the invention is hardly, if at all,noticeable, for

the reduction of illumination is almost in: appreciable. However, to anobserver within the range of the cone of light emitted by the headlightall blinding glare is absent. The presence of the ground glass of anarea not only greater in circumferential extent than 180 degrees, buthaving a drop portion of a form to leave an arc-shaped clear opening inthe lower portion of the headlight front, which opening has acircumferential extent of less than 180 degrees, hides from the eye ofthe observer all glare spots or glare areas due either to the directrays of light from the light unit within the headlight or glare spotsdue to reflection of the light from the reflector oi the headlight. Allthe observer sees is a soft light wholly unobtrusive to the eye andhaving none of the blinding ell'ccts so noticeable in the ordinaryheadlights. The observer is moreover enabled to see quite clearly beyondthe approaching vehicle and so avoid all danger of accident.

l sually the headlights of automobiles and similar motor vehicles arenot more than three or four feet above the roadway, so that the eye ofthe usual observer is conside'ably higher but it is necessary in orderto prevent reflection glares to have the drop portion l of the lightdillusive device low enough to prevent any rays of light di rccted fromthe reflector ot' the headlight from reachii'ig the eye of the observerdi' rectly in front of the headlight. More ottcn, however. the observeris to one side of the axial line of the headlight. wherefore the dropportion must be extended sidewise suliiciently to take care ofreflection glares. Also. the main body of the light dillusive devicemust extend lower than the horizontal diameter of the headlight in orderthat there shall be no distracting glares when the observer is close to.but to one side. of the axial line of the headlight.

.'\ll the brilliant unditlused light emitted from the headlight below ahorizontal line some degrees lower than the horizontal dimurder of theheadlight and outside of an arm still lower than such diameter but notthere reaching to the outer edge of the light emitting end of theheadlight need not be subject to ,ditlusion, but may be utilized in ifull intensity and directness for illumiating the road 'ay t'orpractitally its full lI---;Hiili and many feet in front of the vehirlcsince such an area of light directed at a lowering angle toward theroadway is out of the range of vision of the observer so far as glarespots are concerned. For this rea son the ground glass surface is oiless area than a complete circle so as to leave a prac-- ticallyarc-shaped area for the clear and nondilluscd emission of light of thefull intensity from the headlight where it will brilliantly illuminatethe roadway for so great a. distance ahead of the vehicle as to answerall practical purposes. The ditlusive portion of the headlight openingat the same time causes a strong illumination still fun thcr ahead ofthe vehicle. and at the sides of the roadway to apprise the occupant ofthe traveling vehicle of any o structions far in advance of thecircumscribed area of brilliant illumination. In fact in practice theillumination afforded by a lnradlight of a certain power equipped withthe present invention is not to any marked extent less ellicicnt thanthat afforded by the same l]t?l(l-' light without the present invention.ell'ect. however, upon the observer aprn'oaching the headlight or towardwhom the head light is traveling is very nnirlurdly dii'rren't in thatall obtrusive or blinding glares arc subdued and eliminated, and the eveof the observer is not so affected but that dangers which may be behindthe approaching vehicle can be seen and avoided.

The drop of the downward extension 4 of the ground g ass surface is suchthat should the headlight of the automobile or other vehicle be pointedupwardly with respect to the observer sometimes happens when the vehicleis approaching the top of a hill on one side and the observer is at theother Side of the crown of the hill. both the light giving unit of theheadli ht and portions of the reflector which 11' ht otherwise bevisible are hidden by the ground glass surface in a manner to preventdistracting or blinding glares. Furt n more, no sharp line oi The ldeimircation is produced lit-tween the area of.

extreme brillianiiay and that of dil'lut d ill-uinination, wherefore theoccupant of the ve hiclc is able to readily see lor many hundred feet inadvance of the vehicle all objects which would be visible byll'ik'tll'ltz: oi the headlight were the present invention absent, but aperson or persons aimroaching tae vehicle, or being approached by thevehicle are entirely protected. from the eilects of brilliant andblinding glares.

The present application is a contilnlation of my application No.848,602. filed July 2, 1914, in so far as the general fQlililllQS ot'.the two applications are concerned. the arrange ment of the i'n'esentapplication differing from that of the prior application. in thattheclear inverted are-shaped light emitting area at the. bottom portion ofthe front of the headlight is effectively less. than 180 de grees incircumferential extent. and. at no point reaches as high as the line ofthe horizontal diameter of the light emitting end of the headlight, thisbeing a particularly i111 portant feature of the present invention and.productive of the peculiar and ellecti re-- suits obtained.

\Vhat is claiinei isz 1. In. a headlight projwtor. the Ofillllilllivtion of a reflector so constructed as to pro duce a central lield ofgreat inte 'ty and concentric Zones of varying intensity diminishingtoward the edge thereof. and a glare eliminator adapted to be located infront of the light-giving element and reflector. comprising glass meansliming a, ground glass surface of a form and area to w holly occupy the.upper portion of the lighteemitting front of the headlight for its fullwidth to a line below the horizontal diameter of said front and fromthence as a drop portion of less width than said front and stoppingshort of the bottom thereof to leave a clear area with rising ends atsaid bottom portion, the encroaelnnent of the full-width and dropportions of the ground glass area upon the lower half of the headlightfront being such as to provide a light diffusive shield protecting theeye of an observer from direct view of the light-giving element andthose portions of the headlight reflector productive of intenseillumination. whereby the entire field of light produced by theheadlight is utilizable, for illumination without distractive glare andall intense glare-producing illumi nation is limited to an. area belowthe line. of direct observation under all conditions of practical use ofthe headlight.

2. A glare eliminator for headlights provided with a centrally locatedlight giving element and reflecting means producing zones of reflectedlight surrounding the light source. comprising a plate of glass adaptedto be located at the light emitting end of the headlight and having agroundglass lightdiffusing surface of even texture embracing an arc ofmore than one hundred and eighty degrees with said surface occupying allof the upper half and a fractional portion of the lower half of thelight emitting end of the headlight and provided with a furthercontinuation into the lower half of said front in the form of a drop ofless Width than the first-named portion, the area covered by the groundlass surface and the character of the latter )eing such as to protectthe eye. of an observer in front of the headlight from direct view ofthe source of light and the glare producing Zones of the reflector. andthe area of illumination caused by the headlight remaining unrestricted.

3. An attachment for headlights having light-giving elements andreflectors therein, said attachment being adapted to be applied to theheadlight adjacent to the glass front thereof, and comprising asubstantially segmental sheet of ground glass including an arc of morethan one hundred and eighty degrees and less than three hundred andsixty degrees and provided with an extension from and intermediate ofand less in width than the chord side of the segment, and a ring-shapedcarrier for the sheet of glass extending about the margin of the mainbody thereof and in spaced relation to the extension of said main bodyto there define an arc-shaped clear space free from glass between theprojecting portion of the main bodv and the ring'shaped-carrier, thearea of the ground glass surface including the extension being such asto interpose between the eye of an observer and both the light-givingelement of the headli ht and the areas of intense illumination 0 thereflector of the headlight under all conditions of practical use of suchheadlight.

In testimony that I claim the foregoing as my own, I have hereto afliXedmy signature in the presence of two witnesses.

JOHN EDWARD MORRISON.

\Vitnesses: v

EDNA B. JORDAN,

ALONZO BENNETT.

